@zigedeboo, don't flash any kernels if you going for warranty repair, I *think* i had voided my warranty prior to this whole thing maybe by enabling extras-devel, or when downloading flash software, but anyway portagadgets couldnt give my phone to nokia to fix because of stuff i had done to phone. If i entered imei into nokia site, it said no warranty information available.
Was your car charger a cheap one or good one?

@estel Don't have to worry about posting etiquette too much in this thread, it is a mess. When it finally comes to its conclusion, i'll compile relevant info into first post. I'm wondering if drain on charger (from starter engine pulling current, or stereo pulling current) somehow interacted with phone, but i don't know anything.

There are a whole lot of big copper coils in automotive electrics, and probably a lot of weird inductance stuff goes on when engaging and disengaging starter solenoid. Also lots of capacitance in stereo systems (and speakers), stray electrons looking for atoms to call home, battery in n900 to jump to, dunno.
I had problem with same charger, 2 different cars (one too old for engine computer, one still old but has engine computer, which doesn't work properly and wont hold idle still).
I think my first crash was when playing music with mediabox, output through fm transmitter. 2nd crash I'm not sure if i was playing music or not.

Still, don't know if problem solely due to charger, or something else. BUT me and zigadeboo appear to have exactly the same problem, both phones entered reboot loop instantly. I tried to fix with flash, and failed.

What is really weird is service centre flash can fix, but maemo flash not. I did manage to enable rd-mode for first crash, after flashing, but didn't help. Going to go into linux now and do some more flashing.

That's why I would *love* to see frame-buffer output - to know in which part of booting process it fails exactly. It would be possible to determine filesystem corruption fs software failure vs hardware failure.

On the other hand, I don't want to made anyone warranty attempts harder. Technically, enabling devel or flashing different kernel should not void warranty for N900 - due to nature of device and tools available (using flasher don't void warranty, and You can flash whatever You want - they won't fix broken kernel for You for free, but they *should* fix unrelated issues, even if You played with kernels), but I agree that for most lame service assistants, just seeing backupmenu or framebuffer output would scarry the s.h.i.t out of them, and they're gonna claim You've void Your warranty.

Theoretically, you're able to prove that You still got warranty rights, practically, it may be hard. Of course, flashing back stock kernel - before you take it to repair center - could make them GTFO, but if you won't be able to flash back, by any reasons...

So, I agree here with quokka - although, with much "sadness", cause I like to trace down sources of problems

Also, sorry that I didn't mentioned possible issues with warranty centers, when suggesting framebuffer.

well:not really. thats ballony. maemo has a buggy deamon running that controls charging .... daemon is necessary for hw doesn't work or at least nokia didn't get it working properly. fixes are rare for the whole buggy thing is closed and is not going to be opened by nokia. whatever - OT.

car charger was a cheap one (well it cost £15) but it isnt branded. My first N900 had a simular problem using the charger, the screen stopped working. It would still boot but no screen output. It was replaced under warranty as I was told it couldnt be fixed.

Anyway mines gone for repair, when they do get it into the workshop they'll find it's in R&D mode but I don't think that will void my warranty. I didn't flash the kernal as the battery was completely flat and wouldn't charge in R&D mode.

However if my carrier values me as a customer, then I'd expect it to be fixed. I did have to sign a document that states if it can't be fixed then they will replace with a refurbished phone of simular stauture, which will be tricky as we all know theres nothing else like the N900 on the market. I may except this though, then sell it and buy an N900, safe in the knowledge that in 2 months my contract ends and I can then get something I want.

anyone want to buy a phone car charger?

only flashing a kernel or the system(emmc..) as provided should not void warranty. i did by far more to my phone and would argue i didn't void any warranty.

but trying to solve things that need indepth knowledge is up to the nokia service. nice if people try to help and all. also fine if there are "hackers" around who want to learn the details of a device and are aware that they might break something.

but if one just want to use the phone and get a more complicated issue fixed: nokia(or partner..) is the way to go.

It got nothing to do with hardware non-intelligent (i.e., not speaking with software) over-voltage/over-current protection circuits. But, it's indeed off-topic.

exactly: it is pointless to mention features of a chip if they are bypassed.

Hardware protection circuit isn't bypassed, and isn't features of the chip... Check N900 schematics.

that happened with me once
i fixed it by flashing pr1.2 image then pr1.3 then the emmc

wish it helps

http://focus.ti.com/general/docs/lit...0&fileType=pdf
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